Medium
E01-205 on Biasi Advance Plus 25C

Your boiler has detected an issue related to the domestic hot water system or heat exchanger.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Book a service

This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.

What the manual says

Manufacturer manual

D.h.w. heat exchanger (mod. Advance Plus 30C, Advance Plus 35C)

From this model's manual
Verified against the Biasi/Biasi Advance Plus Service 2012 installation & service manual.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Related fault codes

E01View →E02View →

All 25 fault codes on the Advance Plus 25C

Seeing a different code? Every code this model can display, in one place.

7169-016An 11E01-204E23-792E83-101Er 01Er 02Er 03Er 04Er 05Er 06Er 07Er 08Er 09Er 10Er 11Er 14Er 99H58-661H58-709H74-550H74-553Li 01

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